Chelydridae

Chelydridae Temporal range: 70.6–0Ma PreЄ Є O S D C P T J K Pg N Late Cretaceous[citation needed] to Recent
The common snapping turtle (Chelydra serpentina) a species of Chelydridae
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Testudines (=Chelonii)
Suborder:	Cryptodira
Infraorder:	Eucryptodira
Parvorder:	Polycryptodira
Family:	Chelydridae Gray, 1831[1]
Synonyms[1]
Chelydrae Gray, 1831 Chelydridae Gray, 1839 Chelydradae Gray, 1869

The Chelydridae are a family of turtles which has seven extinct and two extant genera. The extant genera are Chelydra, the snapping turtles, and Macrochelys, of which its larger relative the alligator snapping turtle (Macrochelys temminckii) is the only species. Both are endemic to the Western Hemisphere. The extinct genera are Acherontemys, Chelydrops, Chelydropsis, Emarginachelys, Macrocephalochelys, Planiplastron, and Protochelydra.

Fossil history

The Chelydridae have a long fossil history, with extinct species reported from North America, all over Asia and Europe, far outside their present range. The earliest described chelydrid is Emarginachelys cretacea, known from well-preserved fossils from the Maastrichtian stage of the Late Cretaceous of Montana. Another well-preserved fossil chelydrid is the Late Paleocene Protochelydra zangerli from North Dakota. The carapace of Protochelydra is higher domed than that of the recent Chelydra, a trait conjectured to be associated with the coexistence of large, chelonivorous (i.e., turtle-eating) crocodilians. Another genus, Chelydropsis, contains several well-known Eurasian chelydrid species that existed from the Oligocene to the Pliocene.^{[citation needed]}

Gallery

References

• de Broin, F. 1969. Contribution a l’etude des cheloniens. Cheloniens continentaux du Cretace Superieur et du Tertiaire de France. Memoires du Muséum National d'Histoire Naturelle. Vol. C, No. XXVIII
• Ericson, B. R. 1973. A new chelydrid turtle (Protochelydra zangerli), from the late Paleocene of North Dakota. Scientific Publications of the Science Museum of Minnesota, New Series 2(2):1-16
• Gaffney, E. S. 1975. Phylogeny of the chelydrid turtles: a study of shared derived characters in the skull. Fieldiana Geology, 33:157-178
• Parham, J. F., C.R. Feldman, and J. R. Boore. The complete mitochondrial genome of the enigmatic bigheaded turtle (Platysternon): description of unusual genomic features and the reconciliation of phylogenetic hypotheses based on mitochondrial and nuclear DNA. BMC Evol Biol. 2006; 6: 11. Published online February 7, 2006. doi:10.1186/1471-2148-6-11.
• Whetstone, K. N. 1978. A new genus of cryptodiran turtles (Testudinoidea, Chelydridae) from the Upper Cretaceous Hell Creek Formation of Montana. University of Kansas Science Bulletin. Lawrence, Kansas. 51(17):539-563.

Bibliography

• Rhodin, Anders G.J.; van Dijk, Peter Paul; Inverson, John B.; Shaffer, H. Bradley; Roger, Bour (2011-12-31). "Turtles of the world, 2011 update: Annotated checklist of taxonomy, synonymy, distribution and conservation status". Chelonian Research Monographs 5. Archived from the original on 2012-01-22.